FIB table add/delete API
[vpp.git] / src / vnet / ethernet / arp.c
index 619628b..08e9137 100644 (file)
@@ -22,6 +22,7 @@
 #include <vnet/l2/l2_input.h>
 #include <vppinfra/mhash.h>
 #include <vnet/fib/ip4_fib.h>
+#include <vnet/fib/fib_entry_src.h>
 #include <vnet/adj/adj_nbr.h>
 #include <vnet/adj/adj_mcast.h>
 #include <vnet/mpls/mpls.h>
@@ -109,6 +110,9 @@ typedef struct
 
 static const u8 vrrp_prefix[] = { 0x00, 0x00, 0x5E, 0x00, 0x01 };
 
+/* Node index for send_garp_na_process */
+u32 send_garp_na_process_node_index;
+
 static void
 set_ip4_over_ethernet_rpc_callback (vnet_arp_set_ip4_over_ethernet_rpc_args_t
                                    * a);
@@ -260,7 +264,7 @@ format_ethernet_arp_ip4_entry (u8 * s, va_list * va)
   if (e->flags & ETHERNET_ARP_IP4_ENTRY_FLAG_NO_FIB_ENTRY)
     flags = format (flags, "N");
 
-  s = format (s, "%=12U%=16U%=6s%=20U%=24U",
+  s = format (s, "%=12U%=16U%=6s%=20U%U",
              format_vlib_cpu_time, vnm->vlib_main, e->cpu_time_last_updated,
              format_ip4_address, &e->ip4_address,
              flags ? (char *) flags : "",
@@ -518,6 +522,24 @@ arp_update_adjacency (vnet_main_t * vnm, u32 sw_if_index, u32 ai)
     }
 }
 
+static void
+arp_adj_fib_add (ethernet_arp_ip4_entry_t * e, uint32_t fib_index)
+{
+  fib_prefix_t pfx = {
+    .fp_len = 32,
+    .fp_proto = FIB_PROTOCOL_IP4,
+    .fp_addr.ip4 = e->ip4_address,
+  };
+
+  e->fib_entry_index =
+    fib_table_entry_path_add (fib_index, &pfx, FIB_SOURCE_ADJ,
+                             FIB_ENTRY_FLAG_ATTACHED,
+                             DPO_PROTO_IP4, &pfx.fp_addr,
+                             e->sw_if_index, ~0, 1, NULL,
+                             FIB_ROUTE_PATH_FLAG_NONE);
+  fib_table_lock (fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_ADJ);
+}
+
 int
 vnet_arp_set_ip4_over_ethernet_internal (vnet_main_t * vnm,
                                         vnet_arp_set_ip4_over_ethernet_rpc_args_t
@@ -572,21 +594,9 @@ vnet_arp_set_ip4_over_ethernet_internal (vnet_main_t * vnm,
 
       if (!is_no_fib_entry)
        {
-         fib_prefix_t pfx = {
-           .fp_len = 32,
-           .fp_proto = FIB_PROTOCOL_IP4,
-           .fp_addr.ip4 = a->ip4,
-         };
-         u32 fib_index;
-
-         fib_index =
-           ip4_fib_table_get_index_for_sw_if_index (e->sw_if_index);
-         e->fib_entry_index =
-           fib_table_entry_path_add (fib_index, &pfx, FIB_SOURCE_ADJ,
-                                     FIB_ENTRY_FLAG_ATTACHED,
-                                     FIB_PROTOCOL_IP4, &pfx.fp_addr,
-                                     e->sw_if_index, ~0, 1, NULL,
-                                     FIB_ROUTE_PATH_FLAG_NONE);
+         arp_adj_fib_add (e,
+                          ip4_fib_table_get_index_for_sw_if_index
+                          (e->sw_if_index));
        }
       else
        {
@@ -783,7 +793,6 @@ typedef enum
   _ (opcode_not_request, "ARP opcode not request")                      \
   _ (proxy_arp_replies_sent, "Proxy ARP replies sent")                 \
   _ (l2_address_mismatch, "ARP hw addr does not match L2 frame src addr") \
-  _ (missing_interface_address, "ARP missing interface address") \
   _ (gratuitous_arp, "ARP probe or announcement dropped") \
   _ (interface_no_table, "Interface is not mapped to an IP table") \
   _ (interface_not_ip_enabled, "Interface is not IP enabled") \
@@ -902,8 +911,7 @@ arp_input (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          fib_node_index_t dst_fei, src_fei;
          fib_prefix_t pfx0;
          fib_entry_flag_t src_flags, dst_flags;
-         ip_adjacency_t *adj0 = NULL;
-         adj_index_t ai;
+         u8 *rewrite0, rewrite0_len;
 
          pi0 = from[0];
          to_next[0] = pi0;
@@ -955,52 +963,128 @@ arp_input (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
                                          32);
          dst_flags = fib_entry_get_flags (dst_fei);
 
-         src_fei = ip4_fib_table_lookup (ip4_fib_get (fib_index0),
-                                         &arp0->ip4_over_ethernet[0].ip4,
-                                         32);
-         src_flags = fib_entry_get_flags (src_fei);
-
          conn_sw_if_index0 = fib_entry_get_resolving_interface (dst_fei);
 
-         if (!(FIB_ENTRY_FLAG_CONNECTED & dst_flags))
-           {
-             error0 = ETHERNET_ARP_ERROR_l3_dst_address_not_local;
-             goto drop1;
-           }
-
          /* Honor unnumbered interface, if any */
          is_unnum0 = sw_if_index0 != conn_sw_if_index0;
 
-         /* Source must also be local to subnet of matching interface address. */
-         if (!((FIB_ENTRY_FLAG_ATTACHED & src_flags) ||
-               (FIB_ENTRY_FLAG_CONNECTED & src_flags)))
+         {
+           /*
+            * we're looking for FIB entries that indicate the source
+            * is attached. There may be more specific non-attached
+            * routes tht match the source, but these do not influence
+            * whether we respond to an ARP request, i.e. they do not
+            * influence whether we are the correct way for the sender
+            * to reach us, they only affect how we reach the sender.
+            */
+           fib_entry_t *src_fib_entry;
+           fib_entry_src_t *src;
+           fib_source_t source;
+           fib_prefix_t pfx;
+           int attached;
+           int mask;
+
+           mask = 32;
+           attached = 0;
+
+           do
+             {
+               src_fei = ip4_fib_table_lookup (ip4_fib_get (fib_index0),
+                                               &arp0->
+                                               ip4_over_ethernet[0].ip4,
+                                               mask);
+               src_fib_entry = fib_entry_get (src_fei);
+
+               /*
+                * It's possible that the source that provides the
+                * flags we need, or the flags we must not have,
+                * is not the best source, so check then all.
+                */
+                /* *INDENT-OFF* */
+                FOR_EACH_SRC_ADDED(src_fib_entry, src, source,
+                ({
+                  src_flags = fib_entry_get_flags_for_source (src_fei, source);
+
+                  /* Reject requests/replies with our local interface
+                     address. */
+                  if (FIB_ENTRY_FLAG_LOCAL & src_flags)
+                    {
+                      error0 = ETHERNET_ARP_ERROR_l3_src_address_is_local;
+                      /*
+                       * When VPP has an interface whose address is also
+                       * applied to a TAP interface on the host, then VPP's
+                       * TAP interface will be unnumbered  to the 'real'
+                       * interface and do proxy ARP from the host.
+                       * The curious aspect of this setup is that ARP requests
+                       * from the host will come from the VPP's own address.
+                       * So don't drop immediately here, instead go see if this
+                       * is a proxy ARP case.
+                       */
+                      goto drop1;
+                    }
+                  /* A Source must also be local to subnet of matching
+                   * interface address. */
+                  if ((FIB_ENTRY_FLAG_ATTACHED & src_flags) ||
+                      (FIB_ENTRY_FLAG_CONNECTED & src_flags))
+                    {
+                      attached = 1;
+                      break;
+                    }
+                  /*
+                   * else
+                   *  The packet was sent from an address that is not
+                   *  connected nor attached i.e. it is not from an
+                   *  address that is covered by a link's sub-net,
+                   *  nor is it a already learned host resp.
+                   */
+                }));
+                /* *INDENT-ON* */
+
+               /*
+                * shorter mask lookup for the next iteration.
+                */
+               fib_entry_get_prefix (src_fei, &pfx);
+               mask = pfx.fp_len - 1;
+
+               /*
+                * continue until we hit the default route or we find
+                * the attached we are looking for. The most likely
+                * outcome is we find the attached with the first source
+                * on the first lookup.
+                */
+             }
+           while (!attached &&
+                  !fib_entry_is_sourced (src_fei, FIB_SOURCE_DEFAULT_ROUTE));
+
+           if (!attached)
+             {
+               /*
+                * the matching route is a not attached, i.e. it was
+                * added as a result of routing, rather than interface/ARP
+                * configuration. If the matching route is not a host route
+                * (i.e. a /32)
+                */
+               error0 = ETHERNET_ARP_ERROR_l3_src_address_not_local;
+               goto drop2;
+             }
+         }
+
+         if (!(FIB_ENTRY_FLAG_CONNECTED & dst_flags))
            {
-             /*
-              * The packet was sent from an address that is not connected nor attached
-              * i.e. it is not from an address that is covered by a link's sub-net,
-              * nor is it a already learned host resp.
-              */
-             error0 = ETHERNET_ARP_ERROR_l3_src_address_not_local;
-             goto drop2;
+             error0 = ETHERNET_ARP_ERROR_l3_dst_address_not_local;
+             goto drop1;
            }
 
          if (sw_if_index0 != fib_entry_get_resolving_interface (src_fei))
            {
              /*
               * The interface the ARP was received on is not the interface
-              * on which the covering prefix is configured. Maybe this is a case
-              * for unnumbered.
+              * on which the covering prefix is configured. Maybe this is a
+              * case for unnumbered.
               */
              is_unnum0 = 1;
            }
 
-         /* Reject requests/replies with our local interface address. */
-         if (FIB_ENTRY_FLAG_LOCAL & src_flags)
-           {
-             error0 = ETHERNET_ARP_ERROR_l3_src_address_is_local;
-             goto drop2;
-           }
-
          dst_is_local0 = (FIB_ENTRY_FLAG_LOCAL & dst_flags);
          fib_entry_get_prefix (dst_fei, &pfx0);
          if_addr0 = &pfx0.fp_addr.ip4;
@@ -1035,20 +1119,18 @@ arp_input (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
              goto drop1;
            }
 
-         /* Send a reply. */
        send_reply:
-         ai = fib_entry_get_adj (src_fei);
-         if (ADJ_INDEX_INVALID != ai)
-           {
-             adj0 = adj_get (ai);
-           }
-         else
-           {
-             error0 = ETHERNET_ARP_ERROR_missing_interface_address;
-             goto drop2;
-           }
+         /* Send a reply.
+            An adjacency to the sender is not always present,
+            so we use the interface to build us a rewrite string
+            which will contain all the necessary tags. */
+         rewrite0 = ethernet_build_rewrite (vnm, sw_if_index0,
+                                            VNET_LINK_ARP,
+                                            eth_rx->src_address);
+         rewrite0_len = vec_len (rewrite0);
+
          /* Figure out how much to rewind current data from adjacency. */
-         vlib_buffer_advance (p0, -adj0->rewrite_header.data_bytes);
+         vlib_buffer_advance (p0, -rewrite0_len);
          eth_tx = vlib_buffer_get_current (p0);
 
          vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
@@ -1073,8 +1155,8 @@ arp_input (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          /* the rx nd tx ethernet headers wil overlap in the case
           * when we received a tagged VLAN=0 packet, but we are sending
           * back untagged */
-         memmove (eth_tx->dst_address, eth_rx->src_address, 6);
-         clib_memcpy (eth_tx->src_address, hw_if0->hw_address, 6);
+         clib_memcpy (eth_tx, rewrite0, vec_len (rewrite0));
+         vec_free (rewrite0);
 
          if (NULL == pa)
            {
@@ -1085,9 +1167,11 @@ arp_input (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
                }
            }
 
-         /* We are going to reply to this request, so learn the sender */
-         error0 = arp_learn (vnm, am, sw_if_index0,
-                             &arp0->ip4_over_ethernet[1]);
+         /* We are going to reply to this request, so, in the absence of
+            errors, learn the sender */
+         if (!error0)
+           error0 = arp_learn (vnm, am, sw_if_index0,
+                               &arp0->ip4_over_ethernet[1]);
 
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
                                           n_left_to_next, pi0, next0);
@@ -1483,6 +1567,65 @@ arp_add_del_interface_address (ip4_main_t * im,
     }
 }
 
+void
+arp_adj_fib_remove (ethernet_arp_ip4_entry_t * e, uint32_t fib_index)
+{
+  if (FIB_NODE_INDEX_INVALID != e->fib_entry_index)
+    {
+      fib_prefix_t pfx = {
+       .fp_len = 32,
+       .fp_proto = FIB_PROTOCOL_IP4,
+       .fp_addr.ip4 = e->ip4_address,
+      };
+      u32 fib_index;
+
+      fib_index = ip4_fib_table_get_index_for_sw_if_index (e->sw_if_index);
+
+      fib_table_entry_path_remove (fib_index, &pfx,
+                                  FIB_SOURCE_ADJ,
+                                  DPO_PROTO_IP4,
+                                  &pfx.fp_addr,
+                                  e->sw_if_index, ~0, 1,
+                                  FIB_ROUTE_PATH_FLAG_NONE);
+      fib_table_unlock (fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_ADJ);
+    }
+}
+
+static void
+arp_table_bind (ip4_main_t * im,
+               uword opaque,
+               u32 sw_if_index, u32 new_fib_index, u32 old_fib_index)
+{
+  ethernet_arp_main_t *am = &ethernet_arp_main;
+  ethernet_arp_interface_t *eai;
+  ethernet_arp_ip4_entry_t *e;
+  hash_pair_t *pair;
+
+  /*
+   * the IP table that the interface is bound to has changed.
+   * reinstall all the adj fibs.
+   */
+
+  if (vec_len (am->ethernet_arp_by_sw_if_index) <= sw_if_index)
+    return;
+
+  eai = &am->ethernet_arp_by_sw_if_index[sw_if_index];
+
+  /* *INDENT-OFF* */
+  hash_foreach_pair (pair, eai->arp_entries,
+  ({
+    e = pool_elt_at_index(am->ip4_entry_pool,
+                          pair->value[0]);
+    /*
+     * remove the adj-fib from the old table and add to the new
+     */
+    arp_adj_fib_remove(e, old_fib_index);
+    arp_adj_fib_add(e, new_fib_index);
+  }));
+  /* *INDENT-ON* */
+
+}
+
 static clib_error_t *
 ethernet_arp_init (vlib_main_t * vm)
 {
@@ -1528,6 +1671,11 @@ ethernet_arp_init (vlib_main_t * vm)
   cb.function_opaque = 0;
   vec_add1 (im->add_del_interface_address_callbacks, cb);
 
+  ip4_table_bind_callback_t cbt;
+  cbt.function = arp_table_bind;
+  cbt.function_opaque = 0;
+  vec_add1 (im->table_bind_callbacks, cbt);
+
   return 0;
 }
 
@@ -1538,24 +1686,9 @@ arp_entry_free (ethernet_arp_interface_t * eai, ethernet_arp_ip4_entry_t * e)
 {
   ethernet_arp_main_t *am = &ethernet_arp_main;
 
-  if (FIB_NODE_INDEX_INVALID != e->fib_entry_index)
-    {
-      fib_prefix_t pfx = {
-       .fp_len = 32,
-       .fp_proto = FIB_PROTOCOL_IP4,
-       .fp_addr.ip4 = e->ip4_address,
-      };
-      u32 fib_index;
-
-      fib_index = ip4_fib_table_get_index_for_sw_if_index (e->sw_if_index);
-
-      fib_table_entry_path_remove (fib_index, &pfx,
-                                  FIB_SOURCE_ADJ,
-                                  FIB_PROTOCOL_IP4,
-                                  &pfx.fp_addr,
-                                  e->sw_if_index, ~0, 1,
-                                  FIB_ROUTE_PATH_FLAG_NONE);
-    }
+  arp_adj_fib_remove (e,
+                     ip4_fib_table_get_index_for_sw_if_index
+                     (e->sw_if_index));
   hash_unset (eai->arp_entries, e->ip4_address.as_u32);
   pool_put (am->ip4_entry_pool, e);
 }
@@ -1569,6 +1702,9 @@ vnet_arp_unset_ip4_over_ethernet_internal (vnet_main_t * vnm,
   ethernet_arp_ip4_entry_t *e;
   ethernet_arp_interface_t *eai;
 
+  if (vec_len (am->ethernet_arp_by_sw_if_index) <= args->sw_if_index)
+    return 0;
+
   eai = &am->ethernet_arp_by_sw_if_index[args->sw_if_index];
 
   e = arp_entry_find (eai, &args->a.ip4);
@@ -1593,6 +1729,9 @@ vnet_arp_flush_ip4_over_ethernet_internal (vnet_main_t * vnm,
   ethernet_arp_ip4_entry_t *e;
   ethernet_arp_interface_t *eai;
 
+  if (vec_len (am->ethernet_arp_by_sw_if_index) <= args->sw_if_index)
+    return 0;
+
   eai = &am->ethernet_arp_by_sw_if_index[args->sw_if_index];
 
   e = arp_entry_find (eai, &args->a.ip4);
@@ -1609,7 +1748,11 @@ vnet_arp_flush_ip4_over_ethernet_internal (vnet_main_t * vnm,
        * does in response to interface events. unset is only done
        * by the control plane.
        */
-      if (e->flags & ETHERNET_ARP_IP4_ENTRY_FLAG_DYNAMIC)
+      if (e->flags & ETHERNET_ARP_IP4_ENTRY_FLAG_STATIC)
+       {
+         e->flags &= ETHERNET_ARP_IP4_ENTRY_FLAG_DYNAMIC;
+       }
+      else if (e->flags & ETHERNET_ARP_IP4_ENTRY_FLAG_DYNAMIC)
        {
          arp_entry_free (eai, e);
        }
@@ -1626,6 +1769,7 @@ vnet_arp_populate_ip4_over_ethernet_internal (vnet_main_t * vnm,
   ethernet_arp_ip4_entry_t *e;
   ethernet_arp_interface_t *eai;
 
+  vec_validate (am->ethernet_arp_by_sw_if_index, args->sw_if_index);
   eai = &am->ethernet_arp_by_sw_if_index[args->sw_if_index];
 
   e = arp_entry_find (eai, &args->a.ip4);
@@ -2221,12 +2365,8 @@ arp_term_l2bd (vlib_main_t * vm,
 
        next_l2_feature:
          {
-           u32 feature_bitmap0 =
-             vnet_buffer (p0)->l2.feature_bitmap & ~L2INPUT_FEAT_ARP_TERM;
-           vnet_buffer (p0)->l2.feature_bitmap = feature_bitmap0;
-           next0 =
-             feat_bitmap_get_next_node_index (arp_term_next_node_index,
-                                              feature_bitmap0);
+           next0 = vnet_l2_feature_next (p0, arp_term_next_node_index,
+                                         L2INPUT_FEAT_ARP_TERM);
            vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
                                             to_next, n_left_to_next,
                                             pi0, next0);
@@ -2311,6 +2451,86 @@ ethernet_arp_change_mac (u32 sw_if_index)
   /* *INDENT-ON* */
 }
 
+void static
+send_ip4_garp (vlib_main_t * vm, vnet_hw_interface_t * hi)
+{
+  ip4_main_t *i4m = &ip4_main;
+  u32 sw_if_index = hi->sw_if_index;
+  ip4_address_t *ip4_addr = ip4_interface_first_address (i4m, sw_if_index, 0);
+
+  if (ip4_addr)
+    {
+      clib_warning ("Sending GARP for IP4 address %U on sw_if_idex %d",
+                   format_ip4_address, ip4_addr, sw_if_index);
+
+      /* Form GARP packet for output - Gratuitous ARP is an ARP request packet
+         where the interface IP/MAC pair is used for both source and request
+         MAC/IP pairs in the request */
+      u32 bi = 0;
+      ethernet_arp_header_t *h = vlib_packet_template_get_packet
+       (vm, &i4m->ip4_arp_request_packet_template, &bi);
+      clib_memcpy (h->ip4_over_ethernet[0].ethernet, hi->hw_address,
+                  sizeof (h->ip4_over_ethernet[0].ethernet));
+      clib_memcpy (h->ip4_over_ethernet[1].ethernet, hi->hw_address,
+                  sizeof (h->ip4_over_ethernet[1].ethernet));
+      h->ip4_over_ethernet[0].ip4 = ip4_addr[0];
+      h->ip4_over_ethernet[1].ip4 = ip4_addr[0];
+
+      /* Setup MAC header with ARP Etype and broadcast DMAC */
+      vlib_buffer_t *b = vlib_get_buffer (vm, bi);
+      vlib_buffer_advance (b, -sizeof (ethernet_header_t));
+      ethernet_header_t *e = vlib_buffer_get_current (b);
+      e->type = clib_host_to_net_u16 (ETHERNET_TYPE_ARP);
+      clib_memcpy (e->src_address, hi->hw_address, sizeof (e->src_address));
+      memset (e->dst_address, 0xff, sizeof (e->dst_address));
+
+      /* Send GARP packet out the specified interface */
+      vnet_buffer (b)->sw_if_index[VLIB_RX] =
+       vnet_buffer (b)->sw_if_index[VLIB_TX] = sw_if_index;
+      vlib_frame_t *f = vlib_get_frame_to_node (vm, hi->output_node_index);
+      u32 *to_next = vlib_frame_vector_args (f);
+      to_next[0] = bi;
+      f->n_vectors = 1;
+      vlib_put_frame_to_node (vm, hi->output_node_index, f);
+    }
+}
+
+static vlib_node_registration_t send_garp_na_proc_node;
+
+static uword
+send_garp_na_process (vlib_main_t * vm,
+                     vlib_node_runtime_t * rt, vlib_frame_t * f)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  uword event_type, *event_data = 0;
+
+  send_garp_na_process_node_index = send_garp_na_proc_node.index;
+
+  while (1)
+    {
+      vlib_process_wait_for_event (vm);
+      event_type = vlib_process_get_events (vm, &event_data);
+      if ((event_type == SEND_GARP_NA) && (vec_len (event_data) >= 1))
+       {
+         u32 hw_if_index = event_data[0];
+         vnet_hw_interface_t *hi = vnet_get_hw_interface (vnm, hw_if_index);
+         send_ip4_garp (vm, hi);
+         send_ip6_na (vm, hi);
+       }
+      vec_reset_length (event_data);
+    }
+  return 0;
+}
+
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (send_garp_na_proc_node, static) = {
+    .function = send_garp_na_process,
+    .type = VLIB_NODE_TYPE_PROCESS,
+    .name = "send-garp-na-process",
+};
+/* *INDENT-ON* */
+
 /*
  * fd.io coding-style-patch-verification: ON
  *